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well if you know for sure you have good maf sensor and you have delte the fault codes with a scanner and disconnetec battery for 30 min after you replace the maf to reset ecu and fault comes back next step is to make sure there are no air vacuum leaks if that is all good next step is to remove the intake manifold and replace pcv box and clean throttle

the maf sensor will see and ecu if there is poor air flow thru intake and throttle and clogged pcv very commmon to get dirty

vacuum leaks to check is best if you spray some carburetator cleaner all over the engine and look for any rpm or idle change it will change if there is vacuum leak

As your engine runs, gases from the cylinders leak past the piston's sealing rings into the crankcase. This leaked gas is sometimes referred to as "blow by" because the pressure within the cylinders "blows" them "by" the piston rings. These gases include compounds harmful to an engine, particularly hydrocarbons (unburned fuel), as well as carbon dioxide and water vapor. If allowed to remain in the crankcase, or become too concentrated, the harmful compounds will condense out of the air within the crankcase and form corrosive acids and sludge on the engine's interior surfaces. This can harm the engine as it tends to clog small inner passages, causing overheating, poor lubrication, and high emissions levels. Additionally high pressure in the crankcase can build to a point that leads to a rear main seal failure, an expensive repair. To keep the crankcase air as clean as possible, some sort of ventilation system must be present.

There are different types of PCV systems depending on your car. Some systems use a PCV valve – a one-way valve that ensures continual evacuation of gases from inside a gasoline internal combustion engine's crankcase. Other systems use an oil trap or separator to do the job.

Over time PCV systems and associated tubing can become clogged and fail to vent the buildup of pressure